Pulmonary hypertension in an 18-year-old girl with cholesteryl ester storage disease (CESD)

Lysosomal acid lipase deficiency in pediatric patients: a scoping review

OBJECTIVE

Lysosomal acid lipase deficiency (LAL-D) is an underdiagnosed autosomal recessive disease with onset between the first years of life and adulthood. Early diagnosis is crucial for effective therapy and long-term survival. The objective of this article is to recognize warning signs among the clinical and laboratory characteristics of LAL-D in pediatric patients through a scope review.

SOURCES

Electronic searches in the Embase, PubMed, Livivo, LILACS, Web of Science, Scopus, Google Scholar, Open Gray, and ProQuest Dissertations and Theses databases. The dataset included observational studies with clinical and laboratory characteristics of infants, children and adolescents diagnosed with lysosomal acid lipase deficiency by enzyme activity testing or analysis of mutations in the lysosomal acid lipase gene (LIPA). The reference selection process was performed in two stages. The references were selected by two authors, and the data were extracted in June 2020.

SUMMARY OF THE FINDINGS

The initial search returned 1593 studies, and the final selection included 108 studies from 30 countries encompassing 206 patients, including individuals with Wolman disease and cholesteryl ester storage disease (CESD). The most prevalent manifestations in both spectra of the disease were hepatomegaly, splenomegaly, anemia, dyslipidemia, and elevated transaminases.

CONCLUSIONS

Vomiting, diarrhea, jaundice, and splenomegaly may be correlated, and may serve as a starting point for investigating LAL-D. Familial lymphohistiocytosis should be part of the differential diagnosis with LAL-D, and all patients undergoing upper gastrointestinal endoscopy should be submitted to intestinal biopsy.

Lysosomal acid lipase deficiency allograft recurrence and liver failure- clinical outcomes of 18 liver transplantation patients

Lysosomal acid lipase deficiency (LAL-D) results in progressive microvesicular hepatosteatosis, fibrosis, cirrhosis, dyslipidemia, and vascular disease. Interventions available prior to enzyme replacement therapy development, including lipid lowering medications, splenectomy, hematopoietic stem cell and liver transplantation were unsuccessful at preventing multi-systemic disease progression, and were associated with significant morbidity and mortality. We report two sisters, diagnosed in infancy, who succumbed to LAL-D with accelerated disease progression following splenectomy and liver transplantation. The index patient died one year after hematopoietic stem cell transplant and liver transplantation. Her younger sister survived five years post liver-transplantation, complicated by intermittent, acute rejection. Typical LAL-D hepatopathology, including progressive, microvesicular steatosis, foamy macrophage aggregates, vacuolated Kupffer cells, advanced fibrosis and micronodular cirrhosis recurred in the liver allograft. She died before a second liver transplant could occur for decompensated liver failure. Neither patient received sebelipase alfa enzyme replacement therapy, human, recombinant, lysosomal acid lipase enzyme, FDA approved in 2015. Here are reviewed 18 LAL-D post-liver transplantation cases described in the literature. Multi-systemic LAL-D progression occurred in 11 patients (61%) and death in six (33%). These reports demonstrate that liver transplantation may be necessary for LAL-D-associated liver failure, but is not sufficient to prevent disease progression, or liver disease recurrence, since the pathophysiology is predominantly mediated by deficient enzyme activity in bone marrow-derived monocyte-macrophages. Enzyme replacement therapy addresses systemic disease and hepatopathology, potentially improving liver-transplantation outcomes. This is the first systematic review of liver transplantation for LAL-D, and the first account of liver allograft LAL-D-associated hepatopathology recurrence.

Lysosomal acid lipase deficiency: a form of non-obese fatty liver disease (NOFLD)

INTRODUCTION

With the growing obesity epidemic, nonalcoholic fatty liver disease (NAFLD) is rapidly becoming one of the leading causes of liver disease worldwide. Although obesity is a main risk factor for the development of NAFLD, it can also develop in lean subjects and can be encountered in different clinical setting and in association with an array of genetic, metabolic, nutritional, infectious and drug-induced disorders. Areas covered: This article discusses causes of fatty liver in non-obese subjects focusing on Lysosomal acid lipase deficiency (LAL-D), a commonly overlooked disorder reviewing its prevalence, genetics, pathogenesis, clinical features, diagnosis and treatment. It will also review other causes of non-alcoholic fatty liver disease, which can be encountered in the absence of obesity and metabolic syndrome. Expert commentary: Although the prevalence of LAL-D has been estimated in the range of 1 in 40,000 and 1 in 300,000, this estimate is much more than the identified cases reported in the literature, which suggests that that the disease may be considerably under-diagnosed. There is a pressing need to educate clinicians about the disease, especially with the development of new promising therapeutic modalities.

Managing Cardiovascular Risk in Lysosomal Acid Lipase Deficiency

Lysosomal acid lipase deficiency (LAL-D) is a rare, life-threatening, autosomal recessive, lysosomal storage disease caused by mutations in the LIPA gene, which encodes for lysosomal acid lipase (LAL). This enzyme is necessary for the hydrolysis of cholesteryl ester and triglyceride in lysosomes. Deficient LAL activity causes accumulation of these lipids in lysosomes and a marked decrease in the cytoplasmic free cholesterol concentration, leading to dysfunctional cholesterol homeostasis. The accumulation of neutral lipid occurs predominantly in liver, spleen, and macrophages throughout the body, and the aberrant cholesterol homeostasis causes a marked dyslipidemia. LAL-D is characterized by accelerated atherosclerotic cardiovascular disease (ASCVD) and hepatic microvesicular or mixed steatosis, leading to inflammation, fibrosis, cirrhosis and liver failure. LAL-D presents as a clinical continuum with two phenotypes: the infantile-onset phenotype, formally referred to as Wolman disease, and the later-onset phenotype, formerly referred to as cholesteryl ester storage disease. Infants with LAL-D present within the first few weeks of life with vomiting, diarrhea, hepatosplenomegaly, failure to thrive and rapid progression to liver failure and death by 6-12 months of age. Children and young adults with LAL-D generally present with marked dyslipidemia, hepatic enzyme elevation, hepatomegaly and mixed steatosis by liver biopsy. The average age of the initial signs and symptoms of the later-onset phenotype is about 5 years old. The typical dyslipidemia is a significantly elevated low-density lipoprotein cholesterol (LDL-C) concentration and a low high-density lipoprotein cholesterol (HDL-C) concentration, placing these individuals at heightened risk for premature ASCVD. Diagnosis of the later-onset phenotype of LAL-D requires a heightened awareness of the disease because the dyslipidemia and hepatic transaminase elevation combination are common and overlap with other metabolic disorders. LAL-D should be considered in the differential diagnosis of healthy weight children and young adults with unexplained hepatic transaminase elevation accompanied by an elevated LDL-C level (>160 mg/dL) and low HDL-C level (<35 mg/dL) that is not caused by monogenic and polygenic lipid disorders or secondary factors. Treatment of LAL-D with sebelipase alfa (LAL replacement enzyme) should be considered as the standard of treatment in all individuals diagnosed with LAL-D. Other ASCVD risk factors that may be present (hypertension, tobacco use, diabetes mellitus, etc.) should be managed appropriately, consistent with secondary prevention goals.

Update on lysosomal acid lipase deficiency: Diagnosis, treatment and patient management

Lysosomal acid lipase deficiency (LALD) is an ultra-rare disease caused by a congenital disorder of the lipid metabolism, characterized by the deposition of cholesterol esters and triglycerides in the organism. In patients with no enzyme function, the disease develops during the perinatal period and is invariably associated with death during the first year of life. In all other cases, the phenotype is heterogeneous, although most patients develop chronic liver diseases and may also develop an early cardiovascular disease. Treatment for LALD has classically included the use of supportive measures that do not prevent the progression of the disease. In 2015, regulatory agencies approved the use of a human recombinant LAL for the treatment of LALD. This long-term enzyme replacement therapy has been associated with significant improvements in the hepatic and lipid profiles of patients with LALD, increasing survival rates in infants with a rapidly progressive disease. Both the severity of LALD and the availability of a specific treatment highlight the need to identify these patients in clinical settings, although its low prevalence and the existing clinical overlap with other more frequent pathologies limit its diagnosis. In this paper we set out practical recommendations to identify and monitor patients with LALD, including a diagnostic algorithm, along with an updated treatment.

Sebelipase alfa over 52 weeks reduces serum transaminases, liver volume and improves serum lipids in patients with lysosomal acid lipase deficiency

BACKGROUND & AIMS

Lysosomal acid lipase deficiency is an autosomal recessive enzyme deficiency resulting in lysosomal accumulation of cholesteryl esters and triglycerides. LAL-CL04, an ongoing extension study, investigates the long-term effects of sebelipase alfa, a recombinant human lysosomal acid lipase.

METHODS

Sebelipase alfa (1mg/kg or 3mg/kg) was infused every-other-week to eligible subjects. Safety and tolerability assessments, including liver function, lipid profiles and liver volume assessment, were carried out at regular intervals.

RESULTS

216 infusions were administered to eight adult subjects through week 52 during LAL-CL04. At week 52, mean alanine aminotransferase and aspartate aminotransferase levels were normal with mean change from baseline of -58% and -40%. Mean changes for low-density lipoprotein, total cholesterol, triglyceride and high-density lipoprotein were -60%, -39%, -36%, and +29%, respectively. Mean liver volume by magnetic resonance imaging and hepatic proton density fat fraction decreased (12% and 55%, respectively). Adverse events were mainly mild and unrelated to sebelipase alfa. Infusion-related reactions were uncommon: three events of moderate severity were reported in two subjects; one patient's event was suggestive of a hypersensitivity-like reaction, but additional testing did not confirm this, and the subject has successfully re-started sebelipase alfa. Of samples tested to date, no anti-drug antibodies have been detected.

CONCLUSIONS

Long-term dosing with sebelipase alfa in lysosomal acid lipase-deficient patients is well tolerated and produces sustained reductions in transaminases, improvements in serum lipid profile and reduction in the hepatic fat fraction. A randomized, placebo-controlled phase 3 trial in children and adults is underway (ARISE: NCT01757184).

Impact of the loss of caveolin-1 on lung mass and cholesterol metabolism in mice with and without the lysosomal cholesterol transporter, Niemann-Pick type C1

Caveolin-1 (Cav-1) is a major structural protein in caveolae in the plasma membranes of many cell types, particularly endothelial cells and adipocytes. Loss of Cav-1 function has been implicated in multiple diseases affecting the cardiopulmonary and central nervous systems, as well as in specific aspects of sterol and lipid metabolism in the liver and intestine. Lungs contain an exceptionally high level of Cav-1. Parameters of cholesterol metabolism in the lung were measured, initially in Cav-1-deficient mice (Cav-1(-/-)), and subsequently in Cav-1(-/-) mice that also lacked the lysosomal cholesterol transporter Niemann-Pick C1 (Npc1) (Cav-1(-/-):Npc1(-/-)). In 50-day-old Cav-1(-/-) mice fed a low- or high-cholesterol chow diet, the total cholesterol concentration (mg/g) in the lungs was marginally lower than in the Cav-1(+/+) controls, but due to an expansion in their lung mass exceeding 30%, whole-lung cholesterol content (mg/organ) was moderately elevated. Lung mass (g) in the Cav-1(-/-):Npc1(-/-) mice (0.356±0.022) markedly exceeded that in their Cav-1(+/+):Npc1(+/+) controls (0.137±0.009), as well as in their Cav-1(-/-):Npc1(+/+) (0.191±0.013) and Cav-1(+/+):Npc1(-/-) (0.213±0.022) littermates. The corresponding lung total cholesterol contents (mg/organ) in mice of these genotypes were 6.74±0.17, 0.71±0.05, 0.96±0.05 and 3.12±0.43, respectively, with the extra cholesterol in the Cav-1(-/-):Npc1(-/-) and Cav-1(+/+):Npc1(-/-) mice being nearly all unesterified (UC). The exacerbation of the Npc1 lung phenotype and increase in the UC level in the Cav-1(-/-):Npc1(-/-) mice imply a regulatory role of Cav-1 in pulmonary cholesterol metabolism when lysosomal sterol transport is disrupted.

Cholesteryl ester storage disease: review of the findings in 135 reported patients with an underdiagnosed disease

Cholesteryl ester storage disease (CESD) is caused by deficient lysosomal acid lipase (LAL) activity, predominantly resulting in cholesteryl ester (CE) accumulation, particularly in the liver, spleen, and macrophages throughout the body. The disease is characterized by microvesicular steatosis leading to liver failure, accelerated atherosclerosis and premature demise. Although CESD is rare, it is likely that many patients are unrecognized or misdiagnosed. Here, the findings in 135 CESD patients described in the literature are reviewed. Diagnoses were based on liver biopsies, LAL deficiency and/or LAL gene (LIPA) mutations. Hepatomegaly was present in 99.3% of patients; 74% also had splenomegaly. When reported, most patients had elevated serum total cholesterol, LDL-cholesterol, triglycerides, and transaminases (AST, ALT, or both), while HDL-cholesterol was decreased. All 112 liver biopsied patients had the characteristic pathology, which is progressive, and includes microvesicular steatosis, which leads to fibrosis, micronodular cirrhosis, and ultimately to liver failure. Pathognomonic birefringent CE crystals or their remnant clefts were observed in hepatic cells. Extrahepatic manifestations included portal hypertension, esophageal varices, and accelerated atherosclerosis. Liver failure in 17 reported patients resulted in liver transplantation and/or death. Genotyping identified 31 LIPA mutations in 55 patients; 61% of mutations were the common exon 8 splice-junction mutation (E8SJM(-1G>A)), for which 18 patients were homozygous. Genotype/phenotype correlations were limited; however, E8SJM(-1G>A) homozygotes typically had early-onset, slowly progressive disease. Supportive treatment included cholestyramine, statins, and, ultimately, liver transplantation. Recombinant LAL replacement was shown to be effective in animal models, and recently, a phase I/II clinical trial demonstrated its safety and indicated its potential metabolic efficacy.

Pulmonary Langerhans cell histiocytosis and other pulmonary histiocytic diseases: a review

CONTEXT

Pulmonary Langerhans cell histiocytosis is the most common and best known pulmonary histiocytic lesion; however, the realm of pulmonary histiocytic lesions also includes an assortment of uncommon diseases that may exhibit pulmonary involvement.

OBJECTIVE

To review pulmonary Langerhans cell histiocytosis and other pulmonary histiocytoses to better ensure correct diagnosis and optimal assessment of prognosis and treatment.

DATA SOURCES

Literature review and primary material from the author's institution.

CONCLUSIONS

This review discusses the most common pulmonary histiocytosis, pulmonary Langerhans cell histiocytosis, and also reviews the uncommon pulmonary histiocytic lesions, which are distinct from pulmonary Langerhans cell histiocytosis.

Cholesterol ester storage disease with unusual neurological manifestations in two siblings: a report from South India

Cholesterol ester storage disease is a rare autosomal recessive storage disorder resulting from lysosomal acid lipase deficiency. Two siblings manifested with hepatosplenomegaly, ptosis, and bilateral external ophthalmoplegia. Evaluation revealed hyperlipidemia and bilateral adrenal calcifications. Leukocyte acid lipase levels were significantly low in both the patients, compared with controls, suggesting a diagnosis of cholesterol ester storage disease. Ptosis and external ophthalmoplegia have hitherto not been reported in cholesterol ester storage disease.